Renewable Diesel Acceptable Drop-In Fuel for Ships, Study Finds

Renewable diesel fuel blend made from sugar did not impact ship engine performance or operation, according to a study by the Maritime Administration.

Over a two-week period, MARAD tested the operational, vibration and performance difference of a test vessel’s use of ultra low sulfur diesel versus a blend of diesel and Amyris renewable diesel. MARAD found no significant differences in engine performance, fuel economy, air between the test vessel’s use of neat ultra low sulfur diesel and the blend.

The MARAD study concludes that the renewable diesel is an acceptable drop-in replacement fuel for the State of Michigan ship used in the test as well as other commercial vessels.

MARAD purchased renewable diesel from Amyris for the test. At the time, Amyris only had 1,500 gallons of renewable diesel available, MARAD says in the study. The renewable fuel blend was supposed to be a 50/50 split. An accidental spill resulted in a 67/33 ULSD and renewable diesel blend. MARAD stuck with the new blend because Amyris did not have enough renewable diesel on hand.

The industry will grow to 60.4 billion gallons a year between 2013 and 2017 representing a 3.2 percent annual growth rate, a far slower rate of growth than the 19.6 percent achieved annually from 2005 to 2013, according to the Lux Research report.

The significant industry transition required for novel fuels and feedstocks and challenges including the food vs. fuel debate and blend limits for biodiesel and ethanol will be the primary causes of the decline, Lux says. Next-generation biofuels – such as renewable diesel and butanol – that can offer higher blends, in contrast, are not quite mature, the report says.